Alloy steels



Patented Feb. 28, 1950 ALLOY STEELS William L. Forster, Rochester, Pa.

No Drawing. Application July 31, 1948, Serial No. 41,901

4 Claims. (Cl. 75-125) My invention relates to the manufacture of alloy steels and more particularly to an alloy steel suitable for the manufacture of pipe balls, plugs and. piercing points for sizing seamless tubes, and for other articles which must resist abrasion at high temperatures. Pipe balls or plugs for the sizing of seamless tubes are subjected to considerable abrasion in use. They are thereby reduced in size so that they are no longer suitable for the production of the particular size of pipe for which they are originally designed and must be reground to a smaller size or discarded. It is also important that such balls or plugs be free from objectionable scale formation which might scratch or otherwise mar the internal surface of the pipe making them commercially unfit.

There have been in the past numerous alloys proposed for use at points of abrasion. Such alloys have employed various combinations of alloying elements designated to produce certain desirable characteristics. I have, however, discovered an alloy whose proportions are especially suitable for the production of articles such as pipe balls or plugs and having a use life greatly in excess of any alloys heretofore known.

The alloy of my invention comprises about 1.40% to about 1.75% carbon; about 12% to about 15% chromium; about 3% to about 4.5% nickel; about .60% to about 1.20% molybdenum; about 1.5% to about 2.5% copper; about .20% to about .70% vanadium; less than 1% silicon; about .10% to about .50% manganese; the remainder of the alloy being substantially all iron. There may be, of course, the usual residual amounts of phosphorous and sulphur in the alloy without thereby materially changing its desirable characteristics. In actual practice an alloy steel product according to my invention and having the following analysis:

1.51% carbon 13.15% chromium 3.83% nickel was cast, balance iron annealed, ground and reannealed into pipe balls which when put into use produced three times as many tubes as any pipe balls of which I have knowledge. Pipe balls produced within the range of analysis above given for my alloy will produce similar results. The alloy formed in accordance with my invention may be heat treated to further increase its desirable properties. In practice the pipe balls are cast, annealed at a temperature of 2260", ground and reannealed at a temperature of 1960".

While my alloy has been found to be especially useful in the production of pipe balls and plugs its use is not limited to this alone but will be found equally useful in the production of rolling mill guides and other articles which must resist abrasion at high temperatures, and must be free of objectionable scale pick-up which might mar the surfaces of metallic objects passing over them. While I have disclosed a preferred embodiment of my invention it is to be understood that it is not limited thereb that the invention may be practiced within the scope of the following claims.

I claim:

1. An alloy comprising about 1.40% to about 1.75% carbon, about 12.00% to about 15.00% chromium, about 3.00% to about 4.50% nickel, about .60% to about 1.20% molybdenum, about 1.50% to about 2.50% copper, about .20% to about 310% vanadium, less than 1.00% silicon, about .10% to about .50% manganese, the balance being substantially all iron.

2. An alloy comprising about 1.50% carbon, about 13.00% chromium, about 3.80% nickel, about .80% molybdenum, about 1.60% copper, about 35% vanadium, about .60% silicon, about .20% manganese, the balance being substantially all iron.

3. A pipe ball for use in the manufacture of seamless tube, said ball being made of steel containing about 1.40% to about 1.75% carbon, about 12.00% to about 15.00% chromium, about 3.00% to about 4.50% nickel, about to about 1.20% molybdenum, about 1.50% to about 2.50% copper, about 20% to about .70% vanadium, less than 1.00% silicon, about .10% to .50% manganese, the balance being substantially all iron, said pipe ball being characterized by abrasion resistance, freedom from scale pick-up at high temperatures and having a surface of the character produced by annealing at a temperature of 2260, grinding and reannealing.

4. A steel article suitable for use at high temperatures and resistant to abrasion at said temperatures and containing (having an analysis between) about 1.40% to about 1.75% carbon, about 12.00% to 15.00% chromium, about 3.00% t o 4.50% nickel, about .60 to 1.20% molybdenum, about 1.50% to 2.50% copper, about 20% to .70% vanadium, less than 1.00% silicon about .10% to 50% manganese, the balance being substantially all iron, said article being characterized by abrasion resistance and freedom from scale pick-up at high temperatures.

WILLIAM L. FORSTER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,237,379 Trantin Apr. 8, 1941 2,270,483 Trantin Jan. 20, 1942 FOREIGN PATENTS Number Country Date 590,213 Germany Dec. 28, 1933 Certificate of Correction Patent N 0. 2,499,306 February 28, 1950 WILLIAM L. FORSTER It is hereby certified that errors appear in the printed specification of the above numbered patent requlring correction as follows:

Column 1, line 20, for the word designated read designed; column 2, line 41, for .60 read 60%; line 44, for 50% read .50%;

end that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Ofiice.

Signed and sealed this 80th day of May, A. D. 1950.

THOMAS F. MURPHY,

Assistant Commissioner of Patents. 

1. AN ALLOY COMPRISING ABOUT 1.40% TO ABOUT 1.75% CARBON, ABOUT 12.00% TO ABOUT 15.00% CHROMIUM, ABOUT 3.00% TO ABOUT 4.50% NICKEL, ABOUT .60% TO ABOUT 1.20% MOLYBDENUM, ABOUT 1.50 TO ABOUT 2.50% COPPER, ABOUT .20% TO ABOUT .70% VANADIUM, LESS THAN 1.00% SILICON, ABOUT .10% TO ABOUT .50% MANGANESE, THE BALANCE BEING SUBSTANTIALLY ALL IRON. 